Her comments came as David Cameron was attacked by Ed Miliband during prime minister's questions for having "failed women".

In an interview with Total Politics magazine published on Wednesday evening, Smith acknowledged there was a "new generation" of Conservative women MPs who had a "more of an understanding of the systemic disadvantage that women face in society".

However she added: "Having said that, unless you believe that there's a role for government in promoting gender equality – quite a few of them don’t believe it – I’m not sure you could be a full-blown feminist; they can be feminist-lite, but they aren't proper feminists, because they don’t have an analysis of the system.”

Smith said it was no good politicians complaining that women's pay was unequal with men if they were not willing "to bring in legislation, or take action, in order to put that right".

In 2007 Smith became Britain's first ever female home secretary. She served in the post until 2009 and was then one of Labour's most high profile casualties in 2010 when she lost her seat.

Earlier today Miliband pointed to Cameron's all-male front bench in the Commons as evidence that the Conservatives were not doing enough to deal with the under representation of women in parliament.

"The reason representation matters is because it shapes the policies a government introduces and how they impact on women in the country. He is failing women," he said.

The prime minister said he was proud that under his leadership the number of female Tory MPs had gone from 17 to 48, but admitted the party needed to "do much more".

"On the important issue of getting more women in to public life, this is fantastically important for our country because we will not represent or govern our country properly unless we have more women at every level of our public life."

Of the full cabinet, only four are currently women; home secretary Theresa May, development secretary Justine Greening, Northern Ireland secretary Theresa Villers and culture secretary Maria Miller.

Cameron is also slightly restricted in the proportion of the cabinet that he can make female, as four of the positions are controlled by Nick Clegg. All Lib Dem cabinet ministers are men.